Another seemed uncomfortable when asked if he agreed that China should be more open about social network sites such as Twitter and Facebook.
"Ah, that's ah – well we have to, you know, deal with it from different positions. Because we -- it's -- every government has its own reasons to do."
A student from East China University in Shanghai said the president's speech was unprecedented in their country.
"We can talk freely with him. This is a good chance for Chinese student because maybe in China we not have many chance to speak with high level government leader."
The president was introduced by Hunstman, the U.S. ambassador to China and a former Mormon missionary to Taiwan. Huntsman smoothly addressed the students in English and Chinese.
Obama whispered briefly with Huntsman before he stepped to the podium.
"Nong Hao," the president said -- greeting the students with a local Shanghai slant term for "hello."
"I don't know what he said, but I hope it was good," Obama said of Huntsman's introduction. "I am very sorry that my Chinese is not as good as your English, but I am looking forward to this chance to have a dialogue."